Improvement in slide-valves



A. K. RIDER.

Improvement in Slide-Valves.

[ jPatenfed May 2,1871.4

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duidt mes @sind @fitte ALEXANDER K. RIDER, OF vNEW YORK, N. Y., ASSIGNOR TO HIMSELF, CORNELIUS H. DELAMATER, AND GEORGE H. REYNOLDS, OF SAME PLAGE.

Leners Paterno. 114,344, ,dated May 2, 1871.

IMPROVEMENT IN SLIDE-VALVES.

The Schedule referred to in these Letters Patent and making part of the same.

struction and Operation of Slide-Valves for Steamv 'and other Engines.

The mechanism for operating the valve gives it only a portion of its movement; the remainder oi' its movement is performed instantly bythe action of the steam itself, and its motion is then arrested gently by cushioning on .a quantity of steam.

The following is a description or what I consider the best means of carrying out the invention as applied to thevalve of a steam-hammer,direct-acting, pumping, or an analogous engine.

The accompanying drawing forms a part of this speciiication and represents the novel parts, with so mufch of the ordinary parts as is necessary to indicate their relations thereto.

Figure 1 is a longitudinal section through my improved valve, showing the steam-ports uncovered.

Eigure 2 is a .corresponding section with'the ports covered.

Similar letters of reference indicate like parts lin both the lignres.

'I can use theordinary rectangular steam-chest and slide-valve, with slight modifications, as described further on;but 'prefer the cylindrical steam-chest and piston-valve, which modification of my improvements I will first describe, as follows:

A is the cylindrical steam-chest, and

M audN ports leading to the two ends of the cylnder.

L is the ori'ce through which steam isreceived .by a suitable pipe from a boiler, not represented.

Gis the valve-stem, and l y D is an arm on the piston-rod, which, at or near the'end of each reciprocation, strikes a tappet, C1 or C2, on the valvestem, and gives an end motion there-- 4The piston is marked E, and the piston-rod e.

G is the main valve. It is perforated through its center to allow the easy passage ofthe valve-stem C, and is deeply chambered in a belt around its middle, to allow the steam entering throughl the port Lto have a free admission to either of' the ports, M or N, according as the valve G is at one end or the other of .its motion.

In each end of the valve G there is a shallow cylindrical recess, of such diameter as to receive one of the abutment collars I andJ.

There are, also, oblique openings, y g, communicating from the bottom oi' each cylindrical recess and near the outer acting edges 'of the valve G; the use of this will be presently explained.

It will be understood that the valve G is made to fit steam-tight in the cylindrical steam-chest, as piston-valves are usually made, and thatthe steam iills the belt around the valve, while the space outside of the valve at each end is open to the exhaust.

.HL H2 are the exhaust-ports communicating with an exhaust-pipe, not represented.

I and J are labutment-collars or buffers, firmly fixed on the valve-stem O in the position represented- They are, substantially,circular disks, of such diameterl as to it snugly into the recess in each outer end of the main valve. They are in the drawing represented as having an external flange, tj; but this is not essential to this operation.

These abutment-collars serve three distinct purposes, viz:

First, moving the main valve by contact motion Second, forming an abutment for the steam to react against in continuing the movement of the main valve; and

Third, serving as a cushion-plate to receive the impact of the main valve and gently arrest its motion by cushioning at the end of its movementa There are small oblique parts, g g, arranged as represented. lhese may be formed by drilling one or more holes obliquely in the position shown. They .need not be large, but should be sniicientl numerous to allowa sutiicient flow of steam through heir united areas.

Then the valve G is yat one end of its motion, as shown in iig. l, the steam enters freely through the port N and drives the piston E in the direction indicated by the arrow; but, as the piston E approaches the end of its stroke, thearm4 D, striking thetappet- Cl on the valve-stem C, moves the latter, andzwith it the abutment-,collars I J.' This. motion brings the flange or end, or other portion 'of the piece J, into contact with the corresponding end of the valve G, and commences to move the valve G. This nievement progresses till the exhaust from the main cylinder is arrested, and a little further movement brings the parts into the position indicated in iig'. 2. In this position the strong steam from the port N is freeto leap up through the small port or series of holes g` into the cavity between the abutment-piece 'J and the valve G1 The steam rushing up into this space instantly generates a sutlcient pressure to powerfully separate the abutment J and valve G. As the piece J is fast on the valve-stem C and cannot yield, the valve G moves in obedience to this force, and 'leaps instantly to the opposite end of its throw.' This violent motion is gently arrested by` the cushioning of steam. in the space between the other abutment collar or piece I and the valve G.

In this new position the ports are exposed in the l opposite condition to that-shown in iig'. 1, and the steam is discharged from the end which before re` ceived steam, and is taken in at the end which previonsly discharged it. i The 'consequence is, necessarid ly, a movement of the piston E and its connect-ions in the opposite direction, terminating with a corresponding movement of the valve-stem C and valve Gin the direction opposite to that just described. The movement continues .regularly as long as the engine is worked. I have .in my experiments succeeded in'making,'by this devce,"many hundred strokes a minute with asma-ll engine ot' this construction. g

I would state that, in describing my improvements, I have supposed the steam to be received in the chamber around or between the two heads of the main' valve; likewise, further on, I have supposed a like position of thel steam inlet-passage in describing the rectangular chest and valve modification of my improvement, the exhaust-passages being Aoutside the valve, or toward the ends of the steam-chest. This position of inlet and egress is not essential, as it may be reversed-that is, the present steam-inlet may become exhaust,'and the present exhaust may become inlet, if expedient; but, in that case, the pieces I and J are between the heads of the main valve and face outward;

I claimv as lny ,invention1-- 1. The ports g, arranged to serve, as represented,

in a main valve, G, when the latter itsfitted to movel in the steam-chest, or equivalent casing, so asto complete its stroke by the action of steam received throughthe ports g after the commencement of the `stroke has been initiated by othermeans, all snbstanteally as herein specified. A

2. The pieces I J,1ixed firmly on the valve-stem C, and arranged to operate relatively to'cavities in a main valve, G,`interposed between them so as to receive the action of steam in the small space between themselves and the main valve, to complete the throwA 

